This application relates to the art of couplings and, more particularly, to fluid couplings which are coded such that mating coupling parts intended for one fluid cannot be mated with coupling parts intended for other fluids. The invention is particularly applicable to couplings of the type in which abutting surfaces are held together in sealed relationship by cooperating male and female nuts. However, it will be appreciated that features of the invention have broader aspects, and may be used in other assemblies and for other purposes.
It is broadly known to provide couplings with coded arrangements such that one coupling part intended for one fluid cannot be mated with another coupling part intended for a different fluid. However, satisfactory arrangements of this type have not been available for couplings of the type having abutting surfaces held together in sealed fluid flow relationship by cooperating male and female nuts.